Pre-reform issues, Eastern Sistan. Anonymous. Circa AH 80s-130s / AD 700s-750s. AR Drachm (30.7mm, 3.90 g, 5h). SK (Sistan) mint. Blundered date ('Year 37', but see note below). Obverse margin: Allah wali 'awn / bismillah / rabbi / -. Malek, Arab-Sasanian 957 (same obverse die); SICA 1, -; Album 76.1. Cleaned. Near EF.
While Malek interprets the date on this type as 'Year 37', the style of these coins indicates that they were probably struck half a century later. If the date is meaningful rather than being blundered or stylized to the point of being incomprehensible, and if the unit is indeed '7' (which is by no means certain), it is more likely to be a heavily truncated version of AH 87.